The present invention relates to a device for preventing unauthorised use of card- or disc-shaped proofs of legitimacy and/or data carriers, such as ATM cards, credit cards and flexible discs, comprising a cover- or case-shaped device or the like which has at least one pocket or the like adapted to receive at least a portion of at least one card, disc etc., actuators and control means arranged in said pocket, said control means being adapted to control said actuators and preferably being of the code lock type and comprising one or more means which, when actuated in a certain sequence or in a certain combination, are adapted to control said actuators.
When the present-day type credit cards, which are used as means of payment, fall into wrong hands, they will cause both the card owner and the company issuing the credit cards severe economic damage. Safety programmes proposed and used up to now--e.g. printed stop lists or centralised "on line" stop payment registers--have not proved to be sufficiently effective. Moreover, no solution has been found to the problem of bridging, for the purpose of checking, the frequently long time interval from the point of time at which the true card owner loses his card up to the point of time at which the corresponding information has been entered in a computer file or appears in the stop lists. The time required for distribution of the stop lists, and the risk that such lists are misread or not read at all, must also be calculated.
One object of the present invention is to provide a device which at all times allows the card owner full control of the credit card or the like and which, if the true owner is dispossessed of the card, makes it useless to any other person.
Other types of data carriers, such as flexible discs and the like, may contain information which, if it falls into wrong hands, can cause severe damage both economically and otherwise. Flexible discs with delicate contents are often sent by mail or in some other way between different places of employment, and in such cases, but also through burglary, flexible discs may become accessible to unauthorised persons. With flexible discs and like data carriers, there is a further element of danger in that the disc can be easily copied or made to reveal its contents without the correct receiver noticing this on receipt of the disc. A further object of the invention thus is to provide a device which prevents unauthorised access to the information stored on a disc or the like.
It is previously known to electronically validate credit cards and the like each time before they are used, thereby to prevent improper use. For example, DE-A1 3,131,761 and IBM Technical Disclosure Bulletin, Vol. 12, No. 7, Dec. 7, 1969, p. 969 and Vol. 13, No. 13, Jan. 8, 1971, p. 2140, disclose devices for this purpose. Such devices require, however, that the receiver of the card or data carrier has recourse to electronic equipment indicating whether the correct validating operation has been made, whereas the present invention aims at providing a device by which the card
or data carrier is rendered useless.